Fat embolism

Abstract

Although its original clinical description dates from 1873,¹ fat embolism syndrome remains a diagnostic challenge for clinicians. The term fat embolism indicates the often asymptomatic presence of fat globules in the lung parenchyma and peripheral circulation after long bone or other major trauma. The majority (95%) of cases occur after major trauma. Fat embolism syndrome is a serious consequence of fat emboli producing a distinct pattern of clinical symptoms and signs. It is most commonly associated with fractures of long bones and the pelvis, and is more frequent in closed, rather than open, fractures. The incidence increases with the number of fractures involved. Thus, patients with a single long bone fracture have a 1–3% chance of developing the syndrome, but it has been reported in up to 33% of patients with bilateral femoral fractures.² Fat embolism syndrome can also occur in relation to other trauma, for example, soft tissue injury, liposuction, bone marrow harvest (Table 1). Non-trauma-related causes (e.g. acute pancreatitis, sickling crisis) are less likely to lead to fat embolism syndrome compared with those associated with trauma. An overall mortality of 5–15% has been described.³